Linden



I.. LINDEN.

PROCESS FOR THE COMPLETETREATMENT 0F SEWAGE 0R CONTAMINATED LIQUID.

APPLICATION FILED 55m55.191s.

Mw@ Pufemvd J une 24, m19A @broma m UNITED sTATEs PATENT oEEIoE,

LUcIEN LINDEN, OE LONDON, ENGLAND, AssIe'NOn. To 'WILLIAM' LONDON, ENGLAND.

JOHN STEWART, F

PEOcEss EOE THE COMPLETE TREATMENT OE IsEwAeE on CNTEIIINATED LIQUID. 'e

To all whom it may concern:

Be it known that I, LUCIEN subject of the King'of Belgium, and residing at L6-4:9 Granville House, Arundel street, Strand, London,- W. C. 2, England, have invented a certain new and useful Process for the Complete Treatment .of Sewage or Contaminated Liquid, of which the following is a specification.

This invention relates to the complete treatment of sewage and other contaminated liquids. y

Ilfn .such processes as at present carried out the liquid is frequently obliged to remain completely or substantially stationary for long intervals of time in order that reactions or mechanical sedimentations may be effected. `llhis practice, however, resultsin the actions being slow and imperfect, while the provision of apparatus of large capacit-y becomes necessary and considerable time is required to carry out the treatment.

Now I have found that by modifying thc constructions and proportioning the various parts of the installation with a due regard to theV functions of the remaining parts, the elficiency of each `portion of a combined purify ing plant may be greatly Iincreased with a correspondingly enhanced capacity of output for the size of the apparatus. Furthermore, by performing the various functions of 4the process in different pieces of apparatus especially adapted tol the particular ends in view the time requiredv for each particular function may be considerably lesse cned, and as all the functions are proceeding simultaneously in the combined installation the actual time 'required for the complete treatment of a given quantity of liquid is comparatively short, so much so that for the daily purification of 1,000,000 gallons, the area covered by the plant need not eX- ceed 500 square yards, while 100 minutes is suficient for the passage of liquid through the complete installation. In this way it is possible to complete the treatment of sewage while it is in a comparatively fresh state and before substantial decomposition has occurred, thus rendering possible the recovery of valuable constituents which under ordinary conditions of. working are wasted.

The principal object of the present invention is to provide means for dealing rapidly with large volumes of liquid in apparatus of comparatively small dimensions.

LINDEN, a v

Specification of Letters Patent. l Patented June 24, 1919, Application led September l5, 1918. Serial No. 252,736. v

A further object ofthe invention is to nprovide for 4a quicker and more thorough separation of heavy impurities and those of a greasy nature which are lighter than the r mixture with a reagent, while a sudden rey versa] to ascending movement 1n the presence of suitable directing surfaces in a primary decanting vessel immediately transfers the heavier impurities frointhe moving liquid to a protected quiescent zone facilitating their frequent or continuous prompt re moval, degreasing, clarification, sterilization, aeration and deodorization as required being successively performed by the combined actions occurring during the continuous and comparatively rapid passage of the liquid through' the further units of a combined purifying plant.,

\ The invention further includesV a decano ing tank of the type indicated, in which the liquid in the downwardly sloping conduit is divided into two streams of which the larger, containing the greater portion and the heaviest of the particles, is gradually accelerated on its way to the bottom of the tank where the particles immediately pass between screening surfaoes into a quiescent zone, the other stream passing downward at a gradually decreasingspeed which permits of further separation of the greasy particles which are lighter than, 'and tend to rise in, the liquid from those which on account of their specific ravity also fall between the screening sur aces.

The invention also consists in the improved processes and apparatus for the comf plete treatment of sewage or other liquids as hereinafter described.

The system comprises the preferably violent mechanical mixture of the sewage while in continuous progression in suitable decanting apparatus with one or more purifying or deodorizing agents, the almost immediate precipitatlon of the coarser part of the sludge after it has been broken up and agitated in the act of freeing the fatty substances therefrom, the'l prompt separation of the Iliquid from said sludge deposit and the precipita-tion of the latter by-movement controlled by directing surfaces in a de'canting basm, andthe further immediate passage into a second separatmg tank where the materlal remaining 1n suspenslon 1s further eliminated by downward flow which in coto effect the final purification and to produce water which is clean and imputresci'ble. For this purpose the water is passed through aeration chambers and aerating filters constructed in such a manner as to be capable of being cleaned rapidly and automatically by reversal of the flow of liquid therethrough in order to maintain a high standard of purity, the filter beds serving not only for clarifying the water but also for distributing throughout the mass air or other agents that are considered to be the best suitedfor purifying water, oxidizing it, deodorizing it and eliminating therefrom the agents that have been previously added to it 'or which were originally contained in the sewage.

In carrying the invention into effect in the apparatus shown lby way of example in the accompanying diagrammatic drawing, the sewage or the like is conveyed by a conduit a to. a chamber b having a cover b3 provided with a Ventilating shaft b4.

.In theconduit or pipe a is a connection c for adding to the sewage a reagent such as hypoehlorite of lime. The conduit a, after an abrupt turn, is directed downward in the center of the chamber b, the downwardly directed portion being of an increased cross-sectional area and provided with bafiies or. directing surfaces a, a2, which cause constant abrupt deflections of the liquid in its path downward, thus causing a constant agitation and.

disturbance of the liquid which effectually breaks up into small particles all the solid matter in suspension therein. Readily removable doors a3 are provided upon the sides of this portion of the conduit to afford access for cleaning the directing surfaces and dislodging therefrom any deposit-which may accumulate. At the bottom of the downwardly directed portion of the conduit are a further series of vertical directing surfaces a* for the purpose of imparting a vertical downward direction to the solid particles leaving the bottom of the conduit. The solid particles pass onward through a further series of directing surfaces b in the lower portion of the chamber I), while the liquid now freed from a considerable portion of the solid matter rises in the chamber and overfiows into the collectin trough b2. The solid matter or sludge co lects in the restrict-ed lower portion of the chamber b below the surfaces b and is pumped or lremoved therefrom in any other convenient manner to a receptacle where it may be subjected to further treatment as desired.

The liquid overflowing into the trough b2 passes therefrom by a suitable conduit and is conveyed by mains to the inlets d', d2, of the lsecond depositing or settling tank d, which may be of the form hereinafter described or of other suitable kind as, for example, that described in my United yStates Patent No. 1024451.

The tank d, as shown in the drawing, has a cover d3 provided with a Ventilating shaft d4 and its opposite ends at which the inlets are situated incline downward to restricted receptacles or pockets d5, d, provided in the bottom of the tank. The pockets d, d are protected from the disturbing action of the liquid moving in the tank by a series of direct-ing surfaces (i7, als, and provision is made at the bottom of these pockets for removal of the sludge as in ythe case of the chamber b hereinbefore described.

Substantially parallel with the inclined end surfaces d", d1", are partitions c, e', extending from just below the cover d3 of the tank to just above the tops of the pockets d d. These partitions provide a wide downwardly directed conduit at each end of the tank d which conduits may be each further subdivided into two by the partitions c3, c4, so arranged that while the cross-sectional area of the two outer conduits decreases from the top to the bottom, thecross-sectional area of the two inner'conduits increases in substantially the-same proportion.

The inlets fl', (l2, enter immediately above the openings of the outer conduits, which, being at their tops of considerably greater width than the two inner conduits, consequently receive the greater portion and heaviest of the particles. The liquid entering at the inlets d', d2 ,flows down the two conduits formed by the partitions and the inclined ends of the tank, the lower or heavier ortion of the streams -of liquid passing r own the lower conduits and having their speed gradually increased. while the upper or lighter portion of the liquid passes down the inner conduits with a consequent gradual decrease in its velocity. The particles. of which most are in the outer conduits` are. carried down by the increasing velocity and delivered through the directing surfaces d or cls-into the quiescent zones existing in i vthe pockets d'2' d, Where theirfurther disturb'ance is prevented, while a 'further quantit of .part1cles will,v due to thedecreasingp ve ocity, settle out of the liquid-passlng down the inner conduits andy-alsa fall through the directing surfaces-into the 'colf. lecting pockets. The liquid rising from the endsj'pf the-downwardly directed conduits.

'and carrying with it the greasy particles which are of aless specificgravity than the liquid itselfgasses through screens orgrids du, du, plac horizontally between the ends oit the partitions e and e andthe central division between the pockets (Fand d". The L screens d, d, are pivotally mounted abouttheir .central axis So that they may be oonveniently swung into a vertical position for the rpose of reversing 'or cleanin them.

Agdlut the middle ofthe incline partitions eande are situated vertical partitions e5; c, rising to-a shortdistance `below thek normal level of the liquid in the tank d, and situated a short distance 'upon the outer side of these vertical partitions are further vertical partitions e7, es, the bottoms ofwhich.

are' situated collecting troughs f, f', into which the liquid from the tank overiqws and passes out through the outlets f2, f3. The seals thus formed, while allowing liquid of a certain density to leave the tank, trap the lighter material or fatty substances which are ioating upon the surface of the liquid and when these have accumulated to a depth at which they may be liable vto:.pass the seals they are removed through the col lecting troughs g, g', by momentarilygclosingfthe outlets f2, f3, and allowing the level of liquid in the tank to rise above the edges of the troughs. As soon .as the whole or any desired portion of the fatty substances has been removed.,y the outlets f2, f3, are again opened and the liquid again sinks to the normal working level.`

The' operations which take place in the tankd maybe explained as follows :-V

tti

dill

` under the inlet pipe 0l.

part of the liquid will flow through the irst mentioned passage? such part carrying the wider assage, namely the passage between Z9 an es, and this passage 'tapers vdown-A wardly, so that the sewage in goin downwardly through said passage will ow at a successively increasing rate 'of speed. The said passage is much wider lat the top than the passage between e and e3, and also the.

first mentioned 'paage is located directly Accordingly one rnajbr,V artv .of the solids, especiall the heav1er-sol1ds, 1n the liquld sewage, ue to the Vtendency of the solids to fall, by gravity,

vertically.v As' the liquid after iowingthrough this first mentioned passage leaves ,fthe lovi'erV end thereof, Ja great amount of i'IEfthefheaVy vsolids'in-'the sewage will drop y downwardly through the grating J7.

The liquld flowing through the inclined .passage between e and e will carry (in proportion to its volume) a much smaller per- 'centage- .of solids than-the liquid iowing through 4such irst mentioned passage.l This i liquid.- must iow at a progressivelyslower 'speedin this second mentioned passage, since said-passage flares ina downward direction, and 4on account of this flaring, and also on account of the slowin Aso down of 'its speed,

there is opportunity a orded for sedimentation, that is to say the solid material carried v4in the Aliquid iowing through this second mentioned zpassage tends to drop out of the liquid and eventually through the grating J7. .The liquids fromboth of these passages reunite and flow into the main receptacle, but donot carry a great deal of the' solids, these havin rise to the surface of the liquid. y

The water of the sewage issuing from the outlets f2, f3, has now been freed from the whole of the coarserandmediumsized particles -of solid matter andfatty substances,'

but it will still retain in suspension some of the lighter solid particles' and any foreign liquids originally present or added in the form of reagents." Y

. From the outlets f2; f, the water passes. by the inlets f4, f5, to one or both of the decanting tanks h, h', which are in communication attheir lower ends with chambers h2, it, containing filtering beds M, h5. The filtering beds are supported upon suitable per-v `forated. trays and beneath them and in the decanting tanks h, h', arearranged pockets provided with sludge removal means for collecting and removing any further deposit of dropped below the screen, asv Y above state' During the slow upward flow in the central compartment, fats and the like stantially still lor stagnant liquid beneath V the filters. f rlhe pipe d is located directly above the Thel material forming the lteringbeds h4, h5, contains iron in a suitable form, pref,- erablyk iron ore, and the action of the hypo- 'chlorit'e still in contact with the water is then combined with the action of the iron to' complete the sterilization and deodorization..

From the chambers h2, h3, the liquid passes into further contact and decanting tanks i, z", in passing through Thich a cer-1 tain time is allowed for contact with the reagents and completing the reactions.

On reaching th bottoms'of the Contact tanks i, z", the water passes into the downturned ends of connecting pipes j, j', the further 11p-turned ends of which are situated in the final aerating filter chambers The yconnecting pipes j, j', have a central portion of considerably increased cross-sectional area, and to this portion air or other gaseous fluid is delivered in suitable quantities by the pipesjz, js. The connecting pipes j and j are given an upward inclination to- Jward the chambers la, lo', and the downturned inlet ends of the pipes act as seals to prevent the air or other gaseous medium the reagent. Between the pebble beds and outlet ends ofthe pipes j, j, horizontal perforated grids k2, k3, or the like are inserted to afford further assistance in thoroughly mixing the air or other gaseous medium with the water. If desired, pipe connections as shown dotted at j* and i5 may be provided for deliveringa certain amount of air or the like into the bottom of the aerating filter chambers for further agitating the liquid therein. The filter chambers lc and c communicate with a central outlet chamber l in whichthe main outlet m for purified water is situated. The chamber l is also provided with a drain-ofi' connection l1/and provision is also made in the bottoms of the chambers z', i', c and le for easily removing any solid matter which may accumulate in 4the restricted bottoms thereof.

The two sets of vessels h, z', c, and h', i', c,

, l with the outlet preferably in the center between two or more beds. may be used simul-J taneously or alternatively, and in the event of the filtering beds requiring -cleaning a portion of the purified water which has passed through one set of chambers may b e taken in the reverse direction through the other set and run to waste through the sludge removal means in the bottoms of the chambers h or h in such a manner that the filtering materials are washed by the already purified water. Further, the chambers i and i', if desired, may be omitted and a suitable conneetingpipe having an efficient dip seal to prevent the escape of' the gaseous aerating medium maybe provided to lead the water from the upper portions of the chambers h2,

h3, to the lower portions of the chambers lo, lo.

l in breaking up any contained solid by turbulence created in the flowing liquid, eliminating the heavier particles by throwing them beyond a protective screen of baffles, dividin the current into two streams, of which t ie one containing the greater mass of remaining particles is accelerated downward, while the other is retarded, reuniting saidv streams and causing the combined stream to flow slowly upwardly, separately drawing off the particles of lower specific gravity than the sewageafter such material has risen to the surface of the liquid and filtering the liquid to remove the remaining impurities.

2. A" systematic complete treatment of sewage or other contaminated liquid, which comprises successively the yfollowing steps; first, t-he turbulent flow of the fresh sewage against several abruptly deflected surfaces, relative to the direction of the flow of the liquid, to break up the solid matter and to mix the sewage, second, subjecting the mixeil material, in a plurality of separated streams to flow in a downward direction, one stream containing the larger and heavier part of the solid matter being caused to flow at a const-ant] increasing speed while another portion o the sewage containing relatively less solid matter is caused to flow at a constantly decreasing speed, whereby a considera-ble part of the heavy solid matter in the liquid leaves the liquid, third, causing such solid matter to collect in a screenedofl' relatively quiescent portion of the sewage under treatment, while causin the liquid to rise slowly, whereby particles of material of lower specific gravity than the sewage are caused to rise to the surface, fourth, separatin from the sewage the heavy particles a ove referred to and the light material above referred to, fifth, drawthereafter separating the 'sewage into two 130 Lacasser portions, and causing the one of these por tions to flow downwardly at aconstantly increasing rate of speed, while-causing another portion carr ing proportionately less solid matter to ow downwardly at constantly decreasing speed, said two portions .being ykept separate from each other dur v ing said action, then. reuniting the two streams and causing the same to rise ata speed slower that 'the speed'of liow 1n the preceding operation, whereby at about the end of the downward movement, a largel, proportion of ,heavy solids is removed from tion of the impurities heavier than the sewy y p age and the impurities lighter than the sewthe sewage and whereby during the upward movement a lar e proportion of the material of lower speci c gravity than the sewage is ycaused to rise tothe surface of the sewage.

4. In the treatment of sewage the herein described process which comprises'the steps of dividing the sewage into two fractions,

the one of which contains a proportionately y greater percentage of heavy solids than the other, causing 'such first mentioned fraction to -How in a downward direction ata con- A staiitly increasing speed, while causing thev smaller of saidfractions to ow downwardly at aconstantlyv decreasing speed, then reuniting' the said two streams and allowing Y the fatty material contained in the sewage to rise to thepsurface thereof.

5. A process which comprises thoroughly mingling a chloridizing reagent with the'y sewage, separatin atleast the major porage, 'such operations being conducted in the dark, thereafter subjecting the sewage to iiltration through iron ore, and finally aeratl ing and filtering the sewage.-

6. An apparatussuitable for the'complete treatment of sewage comprising a sewage inlet, a baffle conduit through which the sewage is caused to flow, a sedimentation tank having a plurality of downwardly extending passages separated through their entire length, at least one of which tapers downwardly, and at least one other of which increases in size downwardly, and having an 4.

' upwardly 'extending flaring large passage Gli communicating at its lower end with said downwardly extending passages, an up-iiowl atleast one other of which increases in size downwardly, and having a large chamber communicating with the lower ends of said 'downwardly extending passages, a sewage inlet' from said baiied conduitlocated over said tapering passage, a screen of `substantially vertical plates located in said sedimentation tank below the junction of said downwardly extending passages with said chamber and a sludge outlet below said screen.

8. An apparatus suitable for the eom'- plete treatment of sewagecomprising a bafed conduitthrough which the sewage is caused to fiow, a sedimentation tank having a plurality of downwardly extending passages, at least'one of which tapers downwardly, and at least one other of which increases in size downwardly, and a sewage inlet above said tapering passage, such tank also having a large passage communicating with the lower ends with saiddownw'aidly extending passages, weirs locatedin the upper part of said upwardly extending passage for preventing the fatty material carried upon the top of the liquid therein from flowing away with said liquid, a trap into which the sewage flows from said upwardly extending passage, and a sewage outlet from said trap, an up-low iilter containing a mass of iron ore, another up-iiow filter with an air inlet below the same, and connections connecting said elements in the order mentioned.

9. In an apparatus for the treatment of sewage, the combination of a tank narrower at the bottom than at the top, a baille arranged therein, of which the lower end is vnearer tothe wall of said tank than is the upper end, for-ming a passage tapering downward, anotlierbaiiie spaced from said rst men-tioned baiie, of .which the upper end is nearer to said firstmentioned baiiie than is the lower end, formi-ng a second passage Haring downward, both of said baliies l extending from just below the vliquid level in the tank to near the'lower end of'said tank, a sewage inlet located in said tank directly a'bove the iirst mentioned passage, a

screen dividing the tank into upper and lower compartments at alevel slightly below the lower end ofsaid ta ering passage, and an upwardly extending aring compartment in said tank communicating at its lower en'd with said two passages.

10. ln an apparatus for the treatment of sewage, the combination of a tank narrower at the bottom than at the top, a baffle arranged therein, of which the lower end is nearer to the wall of said tank than is the upper end, forming a passage tapering downwa-rd, another-baffle spaced from said firstinentioned bafiie, of which the upper end is nearer to said first mentioned baffle than is the lower end, forming a second passage Haring downward, both of said baiiies exa sewage inlet located above the said downvwardly tapering passage, a screen dividing the tank into upper and lower compartments at a level slightly below the lower end of said tapering passage, and an upwardly extending rela-tively large compartment in said tank communlcating vat its lower end with said two passages, a VWeir in the upper part of said compartment for allowing liquid sewage to fiow to a. sewage outlet but to prevent grease iioating thereupon from flowing therewi-th, and a separate grease outlet from said compartment.

11. In the purification of sewage, the herein described improvement which comprises passing the se'W-age in a downward direction, as two separated currents, one of which containing a relatively large portion of the solids, Hows with a constantly increasing velocity, and the other of which, containing only a relatively small fraction of the solids flows with 'a constantly decreasing velocity,

2B llwhereby when the said two currents reunite v caused to separate therefrom, causing such v a considerableY proportion of the solids carried by said first mentioned current yare currents to ow slowly as a relatlvely large body so that grease in the sewage can rise to the surface thereof,

1Q. In the purification of sewage, the herein described improvement which comprises passing the sew-age in a downward direction,

as two separated currents, one of which Hows with a constantly increasing velocity, and the other of which flows lwith a constantly del creasing velocity, keeping said two currents separate from each other, thereby allowing a considerable proportion of the solid matters to separate from the sewage, causin such solid matter to fall into a screened-oi relatively quiescent body of liquid to remain separated from the liquid, reuniting said two currents, causing the liquid to slowly rise, so that grease in the sewage can rise to the surface thereof, and separately drawing off grease and the partially purified sewage.

In testimony whereof I have signed my name to this specifica-tion. v LUCIEN LINDEN. 

